The substitute teacher

A substitute teacher walks into the classroom on the blackboard she sees a message. It says, “Jimmy Poole, has got the biggest tool, in the whole damn school!”
She yells, “Whose Jimmy Poole?”
This kid in the back stands up and says, “I’m Jimmy Poole.”
“Well, Jimmy, your staying after school!”
The very next day when the substitute teacher walks in, she looks up at the blackboard and written on it, it says,